Migrating confluence import to nested pages creates empty pages in hierarchy

Steps to reproduce:

• import small confluence space with three small pages (level 1 page, level 2 page, level 3 page)  into XWiki
• after import, the hierarchy is lost and all pages are on the same level
• use nested pages migration tool on imported space
• hierarchy is created correctly, but the pages in the hierarchy are empty

I'll attach the mini-export I used for the test.

For larger spaces this makes the import function unusable because manual reordering of the pages would be too much work.